Field of the Invention
The present invention relates to image processing, and, in particular, to an exposure control system and an associated exposure control method capable of adjusting the current exposure mode according to a long-exposure image and a short-exposure image.
Description of the Related Art
The dynamic range captured by internal optical sensors in cameras or video recorders on the market is about 1000:1 (i.e. the ratio of the brightest pixel to the darkest pixel). The dynamic range captured by optical sensors in professional cameras or video recorders is usually within 10000:1. However, the dynamic range of a common indoor scene is over 2000:1, and the dynamic range of a common outdoor scene is over 1000000:1. In other words, the optical sensors in the aforementioned cameras or video recorders can only capture a portion of the information of the scene.
Generally, a conventional exposure control system adjusts the average brightness value of the whole image to a predetermined brightness value set by the user, but the image effect is not good for dynamic images having a high dynamic range. Accordingly, there is demand for an exposure control system and an associated exposure control method to solve the aforementioned problem.